Oil-tank expansion joint



Ap 1930. c. F. H; BOHNHARDT OIL TANK EXPANSION JOINT Filed Dec. 5; 1928 2 Sheets-Sheet l r .w m W I A ril 1 1930.. c. F. H. BQHNHARDT ,1 4, 97

OIL TANK EXPANSION JOINT Filed Dec. 5, 1928 2 Sheets-Shet 2 Patented Apr. 15, 1930 I UNITED STATES PATENT? o en emulates 1-. n. nonnnannrr, or LYNWOOD, cemron'nm, Assremon 'ro JULIAN A.

: CAMPBELL, or LONG BEACH, cemronma OIL-TAN K EXPANSION J 01m:

This invention relates generally to tubular expansion joint pipe connections, and is particularly concerned with a liquid seal expansible type of joint especially adapted for use 5 in oil tank structures between floating roofs,

and fluid delivery or sampling lines extending into the tank through the roof.

In theuse of storage tanks for containing petroleum oils, it is desirable that theoil inlet line to the tank open thereinto at a suitable point in the roof rather than at the bottom of the tank. This provision is-made in order that should a break or leak occur in the inlet line, or should the pump for deliveringoil through that line become stalled, there will be no ossibility of the oil'contained in the tank backing out or exerting pressure in the inlet line, since the point of introduction to the tank is above the liquid level. j Obviously this may readily be done in a tank having a stationary roof, but difliculties are encountered when it isattempted to pump into a tank through a vertically movable roof such as various types of floating roofs commonly used. It is a purposeof my inventlon,

therefore toprovide an expansible joint between suc vertically movable roofs and a vertically extending and relatively stationary inletline or stand pipe within the tank, such as will. permit relative vertical movement between the stand pipe and roof. The resent joint is constructed in a manner suc as to prevent not only the escape of vapors from the tank between the inlet line and the roof, but also'to eliminate destructive wear between parts of the joint. The various features of be most clearly understood from the following 40 description of a typical application thereof,

reference being made throughout-the description to the accompanying drawings, in which I Figure 1 is a view in part section and elevation of the present joint as applied to a typical tank floating roof and stand pipe structure, the roofbeing at its'hppermostfloatinglevel and the joint ing positions; U

1 2'is a view generally similar to Fig.1

60 but s owing the floating roof .at a low level parts their correspondtheinvention will inthe tank and the joint parts in an expandedposition and Fig. 3 is an enlarged sectional View of the jOlIlt' and'tank parts in the position of Fig.1. 1 -Referring to the drawings,"numeral 10 indlcates a usual storage tank. for containing petroleum oils, the volatility of which may range within wide limits. The tank is provided wlth a floating roof, generally indicated at F, the roof being adapted to float on the liquid at all times irrespective of the amount of liquid contained within the tank. The various purposes of floating roofs are well known to those familiar with the art and therefore need not be discussed herein. The roof may be of any suitable design, for iniirigda pli'cation on air cooled floating roofs,

e the roof shown therein embodying a plurality of floats or basins, suitably joined, the basins being generally similar to the floating unit 11 'copending' a plication entitled Tank roof structure, file Dec. 5, 1928,Serial No. 324,040. The illustrated seal betweenthe tank and roof embodies an I annular troufgh 13, carried around the outer periphery o the roof the inher wall 13' of the 'troughbeing joined to the outer edge of the float unit and extending upward a considerable distance from the roof.

The outer trough wall 13 is spaced from the provided for forming a seal between the trough and shell to prevent the escape ofv vapors form the tank-to this space. An annular skirt 15, integral with the shell and depending anuary 14, 1928, Serial No. 246,758, 7

stance a type such as described in my copendshown in the present drawings. Suitable"- tank shellas at14, there being suitable means a suitable distance from the horizontal por tion 15,'extends downwardly within trough 13, preferably to a point near its bottom when the floatin roof 1.8 its upperm positi n.

Trough is filled with liquid L for instance water having a small amount non-volatile floating roof and the tank shell, this liquid seal preventing the flow of vapor from space 14 or space S to the atmosphere when the roof is in its upper position.

The seal embodies in addition, an annular sheet 16 spaced from the bottom of the trough bymeans of feet 17. A roller 18 is mounted on the upper end of the sheet and is adapted to engage the tank wall at all positions of the floating roof, the roller instead of a sliding contact bein desirable in order to eliminate friction. pair of flexible fla s 19 of suitable composition, for instance ru ber impregnated canvas, are mounted on the outer orizontal portion 16 of the sheet these flaps serving to engage the shell with suflicient tightness to prevent the escape of vapors from the tank into space S.

It will be seen that should considerable liquid be removed from the tank causing thev floating roof to lower to an extent such that the liquid seal maintained by skirt in trough 13 becomes broken, sheet 16, being submerged at its lower end in li uid L and being in engagement with the tan at its up- 30 per end through the flexible flap, forms an additional seal that is effective regardless of the position of the floating roof.

- A vertical stand pi or conduit 20 is contained within the tan the upper end of the 35 pipe extending throu h the roof, and the expansion 'oint embo the invention is arranged etween the stand pipe and the floating roof in order to unit vertical relative movement of the roof and conduit without undue wear of these members, and also to prevent the escape of tank vapors between the stand pipe and roof at all positions of the roof. The stand pipe rests on the bottom of the tank and is perforated at 20" to permit the dischar of liquid into the tank b way of the stan pipe. It may be stated t at in certain instances itis deslrable to pairof stand pipes for a single each of the pipes havmg connection with the roof as illustrated, and to employ one stand pipe as an inlet line andthe other as a sam le' line within which ..a sampling device may lowered, suitable means being rovided in this instance, of course, for readily access to the interior of the stan pi atits upper end. In order for the stan pipe to be used for purposes of obtaining arepresentative sam le of the tank contents, Ihave' provided per orations 20' alo N the pipe of suitable intervals so'that the quid in the stand pipe at any level is in direct communication with the tank liquid at that level.

-The expansion joint, generally indicated at J, is seen to embody an annular'liquid'container or cup 21, the cup having a fluid tight,

a I a a v positlon and the mucus members of the exjoint towards its lower end at 22, with the floating roof. The cup has a central vertical bore or opening at O, the stand pipe extendin through said bore and being s aced from t e inner wall 21" as at 23. A tu ular skirt 24, of somewhat larger diameter than the inner wall 21 of the cup, is mounted upon the stand pipe at a point 25 above the upper end of the cup. The skirt extends downwardly'within the cup, and is shaped at its lower pose of which will later appear. Vapor pressure beneath the cup or within space 0 is relieved through line 27 which communicates with the space S in the up er interior of the skirt and leads to suitabl e vapor draw-ofl means (not shown). The cup 1s filled to apoint near its top with suitable liquid, referably a non-volatile oil, which, in ad ition to enabling the formation of a liquid seal, tends to preserve the metallic parts of the -joint. It will be understood that the provision of the vapor draw-off 27 may be omitted from the structure in the event the volatility of the liquid is insuificient to war rantits inclusion.

The cup, in the position of Fig. 3, contains a plurality of concentric-and tubular telescopic units 30, provided at their lower ends 'with hook portions 30 extendin around the units, and spaced as indicated, irom the inner wall of the next surrounding unit. The upper ends of the unit are shaped to rovide similar hook portions 30 but forme inside the units, extensions 30 being provided for purposes of forming effective i tween the units when in their'expanded position as will later be seen. Gulde strips 32 are mounted on the hook portions of the units as indicated, the pur ose of these strips bein both to center eac unit in relation to the ad acent units, and to insure that the vertica y op osite hook portions of adjacent units will be larought into en a ement when the joint assumes, its expan e position as will now be described.

-When the floating roof is in its uppermost ansio'n oint are in the position illustrated in ig. 1, a liquid seal obviously is maintained between the stand pipe and cup b virtue of the skirt depending within the 'quid contained within the cup. Assumin now that liquid is drained from the ta in such amount as to cause the floating roof and cup 21 to lower to the osition shown in Fig. 2, 1t is seen that upon downward movement of the roof, the telescopic units first lower simultaneously with the cup. Thus the hook portion on the u rend of the innermost unit 'becomes fitte mto the hook 24 on the lower end of the skirt, as at 35, and the remaining units depend in series from the innermost unit in a similar manner as-the roof lowers. It will be seen that the annular hooks themquid seals be- 75 end to provide an annular hook 24", the purselves have considerabledepthigespecially ment may therefore, in combination satin virtue of it heiextension ortionsefi f an jacent hook member, from eflectivje liquid seals between the units; A" reverse procedure-fol lows when the floating roofrailses, with-{the result that when it reaches its uppermost level the units are again 'colla s'ed within thevcupi" It will be understoo the'drawings ,and description are to be considered merely, as illustrative of and not restrictive on the broader claims appended hereto, for various changes in design, structure and arrangebe made without departing'from the spirit and scope of said claims.

I claim:

1. In a structure of the character described, a fluid container having a top closaid closure, saidjoint preventing fluid es'-' sure, a vertical conduit communicating with the interior of the container and extending through said closure, the closure being spaced from said oonduitand vertically movable relative thereto, and a vertically expansible joint between the conduit and saidclosure, said joint preventing fluid escape from the container between the conduit and topclosure during their relative vertical movement.

2. In a structure of the character described, a fluid containerhaving a top closure, a vertical conduit communicating with the ll'lteIlOI' of the container and extending through said closure, the closure being spaced from said conduit and vertically movable relative thereto, and a vertically expansible liquid seal joint between the conduit and cape from the container betweenthe conduit and top closure during their relativeverti-f cal movement. i i

3. In a 7 structure of thefcliarac'te'r de scribed, a fluid container having a top closure, a vertical conduit communicating with the interior of the container and extending through said closure, the'closure being spaced from said conduit and vertically movable relative thereto, and a vertically expansible liquid seal joint between the conduit and,

fluid es said closure, said joint preventin cape from the container'between the'conduit and top closure during their relative vertical movement and comprising .a series of telescopic members, one' end member of the series being attached to the conduit and the other end member ofthe series being at tached to the closure, and means providing a liquid seal between each two adjacent members of said series.

4. In a structure of the character described, a fluid container having atop closure, a vertical vapor conduit communicating with the interior vof the container and extending through said closure, the closure being spaced from said conduit and, vertically movable relative thereto, a'liquid conduit communicating. with said container and ing with the tank interior,

frol'nfthe container between the vapor eonduit andtopclosure during their relative vertical imo'vement.

v5. Iiia structure of the character described,"a fluid container having a top closure, a vertical conduit communicating with the interior of the container and extending through said closure, the closure beingspaced from said conduit and vertically movable relative thereto, and a vertically expansible joint between the conduit and said closure, said joint embodying a pair of tubular telescopic units surrounding the conduit, the

inner of said units being mounted on the conduit and the outer unit having a fluid tight joint with said closure.

1 "6. A structure of the character described embddyinmaliquid containing tank having a vertically movable roof, a vertical standpipe within the tank and extending through the roof and laterally spaced therefrom, and liquid seal means'between the standpipe and the roof, said iineansembodying an annular liquid container'mounted on the roof and extendingaround the standpipe, and a tubular skirt mounted'on the standpipe and annularly spaced there'irom, said skirt depend- V ing beneath theiliquid in said container.

7.. A structureof the character described a vertically movable roof, a vertical: standpipe within the tank and-extending through the roof andlaterally spa'ced therefrom, and liquid seal means-between the standpipe and the roof, said means embodying an annular "liquid containing cup mounted and extendingaround thefst on the roof dpipe, a tubu-v lar skirt mounted onf tthjst'ndp'ipe and annularly spaced therefrom, said skirt dependembodying a liquid containing-tank having I --;extendi'ng within said vapor conduit through i -thetop closure, and an yexpansible' joint betweenthe vapor conduit and" said fclosure, Tsaid-"jointpreventing the escape-of vapor ing beneaththe liquid in said cup when the I roof is in its uppermost position, anda plurality of tubular telescopic'funits in the cup,

the innermost of said units being adapted to depend from saidv skirt and' the remaining units to depend in series from said innermost unit upon downward movement of the roof.

concentric tubular'telescopic units in said cup adapted to depend in series from the lower end of said slnrt upon downward movement of the roof, and a vapor outlet at the upper end of the skirt for removing tank vafors by way of said annular space.

n witness that I claim the fore oing I have hereunto subscribed my name is is 26th day of October, 1928.

\ CHARLES F. H.- BOHNHARDT. 

